Field of the Invention
The invention pertains to an apparatus for triggering an avalanche by means of an explosive charge, which is conveyed to an avalanche slope and which is detonated therein.
There exists a need to artificially trigger avalanches for safety reasons in upper mountainous regions, especially those that have been developed for skiing. Skiers are naturally exposed to the uncontrolled triggering of avalanches. A similar need to trigger avalanches in a controlled manner also exists where a possible destruction of housing areas, roads, forests or the like is to be prevented, which can be caused by uncontrolled starts of avalanches.
It has become known, heretofore, to artificially trigger avalanches by firing rockets at avalanche slopes. This method, however, has the disadvantage that the target area is reached only with inferior accuracy and that, furthermore, populated areas may be hit. Also, the trigger success (the ratio between the number of attempts and actual triggering of a successful avalanche) is less than satisfactory with such a process. Furthermore, rocket missiles are expensive and, due to the fact that they are characterized as military weapons, the use thereof is, or should be, subjected to legal and contractual limitations.
It has also been known, heretofore, to transport the explosive charges to the target area by means of a cableway system specifically established for the purpose and to detonate the same after delivery. While the accuracy of such systems is superior, the establishment and the maintenance thereof are very costly. The operating costs are further aggravated in that it is necessary to exactly determine those target areas at which the explosive charges are to be detonated, which is effected by measurements during the delivery process. For that purpose, operating personnel must be present at the cableway facility during the delivery of the explosives to the target area. The system is furthermore naturally limited to those areas which is covered by the cableway system.
It has also been known to manually throw explosive charges into avalanche slopes. Since, however, it is most important to ensure the safety of operating personnel, this method can only trigger avalanches to a very limited extent. Also, it is possible to throw explosive charges into avalanche slopes from helicopters. Besides the fact that this method is also costly, it requires weather conditions, in which helicopter flights are possible and admissible. This method, therefore, is subject to large organizational limitations.